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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Die aanspreeklikheid van banke as geldskieters vir skade aan die omgewing : 'n regsvergelykende studie / deur G.C. Muller

Muller, Gert Cornelius January 2004 (has links)
Banks play an increasingly important role in the economy because they are in a position to, inter alia, promote development of the environment by utilising their financial resources. In some instances lenders who took up finance from banks are responsible for damage to the environment. Why should banks that financed projects, in the normal course of events, be held liable for damage to the environment caused by borrowers? The question may be answered by a comparative legal study of the 2002 European Union Proposal for a Directive of the European Parliament and of the Council on Environmental Liability with regard to the prevention and remedying of environmental damage; the Comprehensive Environmental Response Compensation and Liability Act of 1980 (CERCLA) of the United States; Part IIA of the Environmental Protection Act of 1990 (EPA) of the United Kingdom and section 28 of the National Environmental Management Act of 1998 (NEM A). NEMA, has its foundation in section 24 of the Constitution of the Republic of South Africa. It incorporates sustainable development as a tool to harmonise the necessity to develop with the need to protect the environment. At the same time NEMA emphasises the role of the principle of intergenerational equity, which presupposes the duty of the current generation to hand over the earth in a better condition than in which it was received from the previous generation. In the future banks, when finance is considered for projects that may harm the environment, must take environmental as well as economical factors into account. Purely economical reasons cannot be the only relevant factor. Development that is financially sound will have to be weighed up against social factors as well as the impact that it will have on the environment. Section 28 of NEMA places a general duty of care on every person who causes, has caused or may cause significant pollution or degradation of the environment to prevent such pollution or degradation from occurring, continuing or recurring. The persons saddled with the duty of care are the owner, the person in control, or the person who has the right to use land or premises. Banks may, under certain circumstances, be considered to be the owner, person in control, or even the person who has the right use land or premises. The polluter pays principle is introduced by section 28 as a basis for liability but the principle is expanded to include, not only the polluter, but also entities, such as banks, who in no way whatsoever, contributed to pollution or degradation. NEMA affords no protection to banks in cases where banks became owner of land by virtue of their security interest in the property. By following established commercial practices, banks may be held liable for environmental damage caused by their clients or erstwhile clients. The traditional role of banks as financial institutions has to change because of the duty placed on banks by the Constitution and NEMA to act as instruments in the protection of the environment. By exerting their influence and by implementing new procedures banks will be able to draw the attention of prospective clients to the need to comply with environmental legislation. In terms of the 2002 Directive of the European Union, the operator who directs an operation by which damage is caused can be held liable for environmental damage. It is necessary to prove that the bank exercised operational control over the business of the borrower. The 2002 Directive is more restrictive than section 28 of NEMA. CERCLA is the primary federal legislation dealing with pollution of hazardous substances. The Environmental Protection Agency has the authority to recover the costs for the reparation of damage to the environment. After the US v Fleet Factors Corporation decision the position was that banks might be held liable if their involvement with the management decisions of the borrower are such that they are in a position to influence the decisions of the borrower. The Asset Conservation Lender Liability and Deposit Insurance Protection Act of 1996 (ACA) changed the magnitude of the Fleet Factors decision. Provision is made by ACA to exempt lenders who held security in terms of a secured creditor exemption, on the condition that the property is alienated at the earliest practicable commercially reasonable time after acquiring it. The requirement for liability is that banks must exercise control over the day-to-day activities of a borrower. The Environmental Protection Act of 1990 in the United Kingdom states that the owner (other than the mortgagee in possession) is the person who has the right to receive the rent of the property if the property was let out. It includes the occupier of the property. The test is whether such a person is in control of the property. If the inference can be drawn that the lender is in control then it can be held liable for environmental damage. EPA, CERCLA as well as the Directive makes it clear that if sufficient control is exercised by a lender over the business of a borrower it may be held liable for damage to the environment. The emphasis should rather be placed on the ability of banks, generally, to influence borrowers than to hold them liable for damage caused to the environment by borrowers. / Thesis (LL.M. (Import and Export Law))--North-West University, Potchefstroom Campus, 2005.
2

Die aanspreeklikheid van banke as geldskieters vir skade aan die omgewing : 'n regsvergelykende studie / deur G.C. Muller

Muller, Gert Cornelius January 2004 (has links)
Banks play an increasingly important role in the economy because they are in a position to, inter alia, promote development of the environment by utilising their financial resources. In some instances lenders who took up finance from banks are responsible for damage to the environment. Why should banks that financed projects, in the normal course of events, be held liable for damage to the environment caused by borrowers? The question may be answered by a comparative legal study of the 2002 European Union Proposal for a Directive of the European Parliament and of the Council on Environmental Liability with regard to the prevention and remedying of environmental damage; the Comprehensive Environmental Response Compensation and Liability Act of 1980 (CERCLA) of the United States; Part IIA of the Environmental Protection Act of 1990 (EPA) of the United Kingdom and section 28 of the National Environmental Management Act of 1998 (NEM A). NEMA, has its foundation in section 24 of the Constitution of the Republic of South Africa. It incorporates sustainable development as a tool to harmonise the necessity to develop with the need to protect the environment. At the same time NEMA emphasises the role of the principle of intergenerational equity, which presupposes the duty of the current generation to hand over the earth in a better condition than in which it was received from the previous generation. In the future banks, when finance is considered for projects that may harm the environment, must take environmental as well as economical factors into account. Purely economical reasons cannot be the only relevant factor. Development that is financially sound will have to be weighed up against social factors as well as the impact that it will have on the environment. Section 28 of NEMA places a general duty of care on every person who causes, has caused or may cause significant pollution or degradation of the environment to prevent such pollution or degradation from occurring, continuing or recurring. The persons saddled with the duty of care are the owner, the person in control, or the person who has the right to use land or premises. Banks may, under certain circumstances, be considered to be the owner, person in control, or even the person who has the right use land or premises. The polluter pays principle is introduced by section 28 as a basis for liability but the principle is expanded to include, not only the polluter, but also entities, such as banks, who in no way whatsoever, contributed to pollution or degradation. NEMA affords no protection to banks in cases where banks became owner of land by virtue of their security interest in the property. By following established commercial practices, banks may be held liable for environmental damage caused by their clients or erstwhile clients. The traditional role of banks as financial institutions has to change because of the duty placed on banks by the Constitution and NEMA to act as instruments in the protection of the environment. By exerting their influence and by implementing new procedures banks will be able to draw the attention of prospective clients to the need to comply with environmental legislation. In terms of the 2002 Directive of the European Union, the operator who directs an operation by which damage is caused can be held liable for environmental damage. It is necessary to prove that the bank exercised operational control over the business of the borrower. The 2002 Directive is more restrictive than section 28 of NEMA. CERCLA is the primary federal legislation dealing with pollution of hazardous substances. The Environmental Protection Agency has the authority to recover the costs for the reparation of damage to the environment. After the US v Fleet Factors Corporation decision the position was that banks might be held liable if their involvement with the management decisions of the borrower are such that they are in a position to influence the decisions of the borrower. The Asset Conservation Lender Liability and Deposit Insurance Protection Act of 1996 (ACA) changed the magnitude of the Fleet Factors decision. Provision is made by ACA to exempt lenders who held security in terms of a secured creditor exemption, on the condition that the property is alienated at the earliest practicable commercially reasonable time after acquiring it. The requirement for liability is that banks must exercise control over the day-to-day activities of a borrower. The Environmental Protection Act of 1990 in the United Kingdom states that the owner (other than the mortgagee in possession) is the person who has the right to receive the rent of the property if the property was let out. It includes the occupier of the property. The test is whether such a person is in control of the property. If the inference can be drawn that the lender is in control then it can be held liable for environmental damage. EPA, CERCLA as well as the Directive makes it clear that if sufficient control is exercised by a lender over the business of a borrower it may be held liable for damage to the environment. The emphasis should rather be placed on the ability of banks, generally, to influence borrowers than to hold them liable for damage caused to the environment by borrowers. / Thesis (LL.M. (Import and Export Law))--North-West University, Potchefstroom Campus, 2005.
3

DNA damage and repair in nail technicians caused by occupational exposure to volatile organic compounds / N. van der Merwe

Van der Merwe, Nicolene January 2010 (has links)
Objectives: The aim of this study was to determine if exposure to volatile organic compounds can lead to DNA damage and impaired DNA repair capacity. Nail cosmetics is a fast growing industry around the world where employees and clients are subjected to various chemical substances which may be harmful to their health: such as formaldehyde, toluene, acetone, xylene, ethylmethacrylate, methylmethacrylate and n–buthyl acetate. These chemicals have the potential to be harmful to their health and exposure to these chemicals should be actively controlled. Formaldehyde is classified as a human carcinogen by the IARC, whereas, toluene and xylene are group three carcinogens, classified in 1999 (not classified as carcinogenic to humans), and various studies have linked DNA damage and impaired DNA repair to the above mentioned substances. Methods: Fifteen nail technicians were monitored by means of personal air sampling, measuring formaldehyde, toluene, xylene, acetone and ethylmethacrylate exposure. Fifteen unexposed subjects were chosen and matched for age and smoking habits with the exposed group. Heparinised blood samples were obtained from each test subject with which the Comet Assay was performed on lymphocytes to determine DNA damage and repair ability. Results: Exposure to ethylmethacrylates and methylmethacrylates leads to DNA damage. Methylmethacrylate causes DNA damage by specifically targeting pyrimidine (fpg) bases. N–buthyl acetate, xylene and acetone exposure impaired DNA repair capacity. The exposed group showed signs of Class III and Class IV DNA damage, whereas the control group had little Class III damage and no indication of Class IV damage. The overall DNA repair ability of the nail technicians was slightly impaired when compared to that of the control group, which is in concurrence with previous studies. Smoking habits and age did not show significant influences on the level of DNA damage and repair when compared with the control group. Conclusion: Exposure to volatile organic compounds such as ethylmethacryale and methylmethacrylate may lead to DNA damage and altered DNA repair in some individuals, although further studies are recommended. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2011.
4

DNA damage and repair in nail technicians caused by occupational exposure to volatile organic compounds / N. van der Merwe

Van der Merwe, Nicolene January 2010 (has links)
Objectives: The aim of this study was to determine if exposure to volatile organic compounds can lead to DNA damage and impaired DNA repair capacity. Nail cosmetics is a fast growing industry around the world where employees and clients are subjected to various chemical substances which may be harmful to their health: such as formaldehyde, toluene, acetone, xylene, ethylmethacrylate, methylmethacrylate and n–buthyl acetate. These chemicals have the potential to be harmful to their health and exposure to these chemicals should be actively controlled. Formaldehyde is classified as a human carcinogen by the IARC, whereas, toluene and xylene are group three carcinogens, classified in 1999 (not classified as carcinogenic to humans), and various studies have linked DNA damage and impaired DNA repair to the above mentioned substances. Methods: Fifteen nail technicians were monitored by means of personal air sampling, measuring formaldehyde, toluene, xylene, acetone and ethylmethacrylate exposure. Fifteen unexposed subjects were chosen and matched for age and smoking habits with the exposed group. Heparinised blood samples were obtained from each test subject with which the Comet Assay was performed on lymphocytes to determine DNA damage and repair ability. Results: Exposure to ethylmethacrylates and methylmethacrylates leads to DNA damage. Methylmethacrylate causes DNA damage by specifically targeting pyrimidine (fpg) bases. N–buthyl acetate, xylene and acetone exposure impaired DNA repair capacity. The exposed group showed signs of Class III and Class IV DNA damage, whereas the control group had little Class III damage and no indication of Class IV damage. The overall DNA repair ability of the nail technicians was slightly impaired when compared to that of the control group, which is in concurrence with previous studies. Smoking habits and age did not show significant influences on the level of DNA damage and repair when compared with the control group. Conclusion: Exposure to volatile organic compounds such as ethylmethacryale and methylmethacrylate may lead to DNA damage and altered DNA repair in some individuals, although further studies are recommended. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2011.
5

Treitering in Suid-Afrikaanse openbare skole en die regs-en onderwysbestuursimplikasies daarvan vir leerderveiligheid (Afrikaans)

Wentzel, Jan Andries 22 October 2008 (has links)
Navorsingsresultate toon dat treitering ‘n ernstige probleem is wat wêreldwyd voorkom, ook in Suid-Afrika en dat die getal slagoffers wat daardeur geraak word skrikwekkend hoog is. Die doel van hierdie studie is om die regsimplikasies van treitering van leerders deur mede-leerders in Suid-Afrikaanse openbare skole vir die onderwysbestuur en onderwysreg te ondersoek en te beskryf. Met die term “onderwysbestuur” word verwys na onderwys op nasionale vlak, provinsiale vlak en skolevlak. Die regsimplikasies vir die onderwysreg is hoofsaaklik daarin geleë dat daar nuwe kennis tot die onderwysreg toegevoeg word. Dit is aksiomaties dat regsimplikasies onlosmaaklik verbonde is aan regsreëls. Daar kan slegs sprake wees van regsimplikasies van ‘n aangeleentheid as daar regsreëls is wat die aangeleentheid beheer en rig – in die geval van hierdie studie, die regsreëls wat die bestuur en hantering van treitering in Suid-Afrikaanse openbare skole rig en beheer. Die regsreëls wat die bestuur en hantering van treitering in Suid-Afrikaanse openbare skole rig en beheer, is deel van die Handves, internasionale kinderregte-ooreenkomste, wetgewing, die gemene-reg, deliktereg, die strafreg en regspraak. Om die navorser in staat te stel om die regsreëls in ge-noemde regsbronne te identifiseer, is ‘n deeglike kennis van die fenomeen “treitering” noodsaaklik. Om die regsimplikasies van hierdie regsreëls te bepaal, beteken dat hierdie regsreëls binne die konteks van “treitering” as fenomeen geïnterpreteer moet word. Daar moet dus beskryf word hoe hierdie regsreëls toepassing vind met betrekking tot treitering. Die interpretasie van hierdie regsreëls binne die konteks van treitering geskied deur middel van semi-gestruktureerde onderhoude met geïdentifiseerde respondente wat geïdentifiseer is op grond van hul kennis van spesifieke regsdissiplines en die praktyk soos byvoorbeeld menseregte en kinderregte, die gemenereg, die deliktereg, die strafreg, die onderwysreg asook die regspraktyk en onderwysregspraktyk. Die beskrywing van die regsimplikasies vir die onderwysbestuur en onderwysreg is hoofsaaklik gegrond op die response (bevindinge) van die respondente, maar die regsimplikasies word uitgebrei deur die response van die respondente te verbind aan veelvuldige bronne van informasie. Hierdie aanvullende informasie wat aangewend word vir ryker beskrywing (“thick description”) lei ook die navorser tot die identifisering of beskrywing van verdere implikasies wat nie noodwendig in die respondente se response na vore gekom het nie. Die regsimplikasies van die treitering van leerders deur mede-leerders is omvattend en het implikasies vir die onderwysbestuur op nasionale vlak, provinsiale vlak, distriksvlak en skolevlak en wel ten opsigte van die volgende afdelings van die Suid-Afrikaanse reg: fundamentele regte, wet-gewing, die deliktereg en strafreg. ENGLISH: Research results indicate that bullying is a serious problem worldwide, South Africa included, and that the number of victims affected is alarmingly high. The purpose of this study is to investigate and describe the legal implications that bullying of learners by fellow learners in South African public schools has for education management and education law. “Education management” refers to education at national, provincial and school levels. The legal implications for education law lie mainly in the fact that new information is being added to the body of education law. It is axiomatic that legal implications are inextricably bound to legal rules. One can only speak of legal implications if there are legal rules that control and direct them – in the case of this study it is the legal rules that control and direct the management and operation of bullying in South African public schools. The legal rules that control and direct the management and operation of bullying in South African public schools are part of the Bill of Rights, international children’s rights conventions, legislation, common law, law of delict, case law and criminal law. A thorough knowledge of the phenomenon “bullying” was necessary to enable the researcher to identify the legal rules contained in the legal sources mentioned. In order to determine the legal implications of these legal rules, it was necessary to interpret these legal rules within the context of the phenomenon “bullying”. It was therefore necessary to describe how these legal rules are applied with regard to bullying. The interpretation of these legal rules within the context of bullying was done by means of semi-structured interviews with identified respondents who were identified on grounds of their knowledge of specific law disciplines and practice such as human rights and children’s rights, common law, the law of delict, criminal law, education law and legal practices and education law practices. The description of the legal implications for education management and education law is based mainly on the responses (findings) of the respondents, but the legal implications are extended by linking the responses of the respondents with many other sources of information. This supplementary information, which is used to enrich the description (thick description), also led the researcher to identifying or describing additional implications that were not necessarily evident from the responses of the respondents. The legal implications of the bullying of learners by fellow learners, are comprehensive and have implications for education management at national level, provincial level, district level and school level, especially in terms of the following sections of South African law: fundamental rights, legis-lation, the law of delict and criminal law. / Thesis (PhD)--University of Pretoria, 2008. / Education Management and Policy Studies / unrestricted
6

Simulation of tropical cyclone-like vortices over the southwestern Indian Ocean

Mbedzi, Maluta Pennington 25 October 2010 (has links)
Tropical cyclones claim a huge number of lives and cause substantial damage to property and crops in many regions each year. Southern Africa is no exception. This makes the process of forecasting tropical cyclones of great importance to the region’s economy and to public safety. Skillful seasonal forecasts of tropical cyclone activity could be used to warn the communities affected by tropical cyclones of the likely occurrence of such systems ahead of the cyclone season. This could result in reduced damage and fatalities associated with such systems. Both statistical and dynamical techniques have been employed in an attempt to predict tropical cyclone activity on a seasonal time scale over a number of ocean basins. The skills of such techniques vary from one technique to another and from one basin to another. This study investigates the predictability of tropical cyclone activity on a seasonal time scale over the southwestern Indian Ocean (SWIO) by nesting a regional climate model (RCM), the RegCM3 within a coarse-resolution atmospheric general circulation model (AGCM), the ECHAM4.5. The national meteorological centres of most southern African countries do not have the required dedicated computational resources to run the high-resolution GCMs that are suitable to predict these systems operationally. However, these systems can be very devastating on the southern African region and need to be predicted on various time scales, including the seasonal time scale. Therefore, it is instructive that research be done to better our understanding of these systems and their predictability using physical models. This study examines the simulations of the genesis locations and the number of tropical cyclones produced in RCM integrations nested within an AGCM forced by observed sea-surface temperatures (SSTs). The season of interest is the mid-summer period of December to February. Four members of the AGCM generated at the International Research Institute for Climate and Society (IRI) are used to force the RCM. Four-month integrations over a 10-year period (1991/92-2000/01) are performed. An objective procedure for detecting model-generated tropical cyclones is applied to this ensemble. Some characteristics of the simulated cyclones are compared with the observations. In addition, some statistical techniques are employed to evaluate the capability of the RCM to reproduce some aspects of the observed tropical cyclones during the aforementioned period. The results show that there is a good agreement between two of the simulated and observed environmental variables that influence tropical cyclone formation, viz. vertical wind shear and relative vorticity. In particular, the simulated and observed vertical wind shear show a similar pattern in most parts of the model domain. With regards to the relative vorticity, the highest agreement is found in the Mozambique Channel and in the region east of Madagascar. In addition, there is an appreciable agreement between the simulated and observed tropical cyclone characteristics such as tropical cyclone genesis locations and frequency. The model also simulated the interannual variability in the tropical cyclone frequency skillfully. AFRIKAANS : Tropiese siklone is verantwoordelik vir ‘n goot aantal sterftes en veroorsaak beduidende skade aan eindom asook oeste oor etlike areas elke jaar. Suidelike Afrika is nie ‘n uitsondering nie. Hierdie verliese maak die voorspelling van tropiese siklone van groot belang vir die gebied se ekonomie asook vir publieke veiligheid. Vaardige seisoenale voorspelling van tropiese sikloon aktiwiteit kan gebruik word om gemeenskappe wat onderhewig is aan die invloed van tropiese siklone te waarsku oor die kans vir sulke sisteme om voor te kom voordat die tropiese sikloon seisoen ‘n aanvang neem. Vroegtydige waarskuwings kan tot gevolg hê dat daar minder verwant skade en laer sterftes is. Beide statistiese en dinamiese tegnieke is al in die verlede gebruik om tropiese sikloon aktiwiteit oor verskeie oseaankomme op ‘n seisoenale tydskaal te probeer voorspel. Die vaardigheid van hierdie tegnieke hang af van die tipe tegniek wat gebruik word asook watter oseaankom beskou word. Hierdie studie ondersoek die voorspelbaarheid van tropies sikloon aktiwiteit op ‘n seisoenale tydskaal oor die suid-westelike Indiese Oseaan deur gebruik te maak van ‘n streeksmodel, die RegCM3, genes in ‘n growwe-resolusie algemene sirkulasie model van die atmosfeer, die ECHAM4.5. Die nasionale weerdienste van die meerderheid Suider-Afrikaanse lande beskik nie oor die nodige rekenaars om geskikte hoë-resolusie algemene sirkulasie modelle te loop om sodanige sisteme mee operasioneel te voorspel nie. Desnieteenstaande kan hierdie tropiese sisteme verwoestend wees en daarom behoort hulle voorspel te word op verskeie tydskale, insluitende seisoenale tydskale. Dit sal dus insiggewend wees om navorsing te doen om sodoende ons begrip oor hierdie sisteme en hul voorspelbaarheid te verbeter deur gebruik te maak van fisiese modelle. Hierdie studie gaan ondersoek instel oor die simulasie van tropiese siklone oor hul ontwikkelingsgebiede en die aantal tropiese siklone wat ‘n streeksmodel, genes in ‘n algemen sirkulasie model van die atmosfeer wat geforseer word deur waargeneemde see-oppervlak temperature, kan produseer. Die seisoen van belang is die mid-somer periode van Desember tot Februarie. Vier ensemble lede afkomstig vanaf die algemene sirkulasie model wat geloop is by die International Research Institute for Climate and Society word gebruik om die streeksmodel mee te forseer. Model integrasies word oor ‘n 4-maand periode gedoen en vir ‘n 10-jaar tydperk (1991/92-2000/01). ‘n Objektiewe vorteks opsporingsprosedure word dan toegepas op die 4-lid ensemble om model-geskepte tropiese siklone te identifiseer. Sommige van die karakteristieke van die gesimuleerde siklone word dan vergelyk met die waargeneemde tropiese stelsels. Hiermee saam word statisiese tegnieke ingespan vir die genoemde tydperk om die vermoë van die streeksmodel te ondersoek om sekere aspekte van waargeneemde storms te herproduseer. Die resultate wys dat daar ‘n goeie ooreenkoms is tussen twee van die gesimuleerde en waargeneemde omgewingsveranderlikes wat tropiese sikloon ontwikkeling beinvloed, nl, vertikale windskuiwing en relatiewe vortisiteit. In besonder het die gesimuleerde en waargeneemde vertikale windskuiwing ooreenstemmende patrone gelewer oor die grootste gedeelte van die streeks model-area. Wat relatiewe vortisiteit betref, is die beste ooreenkoms oor die Mosambiek kanaal en in die gebied oos van Madagaskar gevind. Verder is daar ‘n sterk ooreenkoms tussen die gesimuleerde en waargeneemde tropiese sikloon karakteristieke soos by die tropiese siklone se ontwikkelingsgebiede asook hul frekwensie. Die model he took daarin geslaag om die inter-jaarlikse veranderlikheid van tropiese sikloon frekwensie suksesvol te simuleer. / Dissertation (MSc)--University of Pretoria, 2010. / Geography, Geoinformatics and Meteorology / MSc / Unrestricted
7

Urinary 1,4–dihydroxynonene mercapturic acid (DHN–MA) and 8–hydroxy–2'–deoxyguanosine (8–OHdG) as markers of oxidative damage : the SABPA study / by Leandrie Steenkamp

Steenkamp, Leandrie January 2010 (has links)
The human body has evolved certain defence mechanisms to cope with the high occurrence of free radicals. These radicals are obtained endogenously from the mitochondria, peroxisomes, the cytochrome P450 (CYP 450) system and neutrophils, or exogenously from the environment. Lack of antioxidants and/or increased production of free radicals will result in oxidative stress, which has been implicated in certain human diseases such as hypertension, inflammation, ageing, autoimmunity, atherosclerosis, Parkinson?s disease, cancer and diabetes. Although the initial aim was to standardise a single assay to quantify both 8–OHdG and DHN–MA, this could not be achieved in this study due to the vast difference in the chemical properties of these two metabolites. Following the decision to use two separate assays for the quantification of the mentioned biomarkers, the 8–OHdG assay was standardised and validated. The intrabatch variation of the assay was 4.18% and the interbatch variation was 17.37%. Unfortunately, the DHN–MA assay could not be standardised within the time frame of this study due to experimental difficulties. Therefore, only urinary 8–OHdG and serum ROS levels were quantified. Urinary 8–OHdG levels were measured in 409 participants (209 Caucasians, 101 males and 108 females and 200 Africans, 100 males and 100 females) from the SABPA study. After removal of outliers from the data matrix, the effect of gender and ethnicity was investigated on the measured urinary 8–OHdG levels. No significant difference in the urinary 8–OHdG levels between Caucasian males (n=87) and females (n=96) were observed (p = 0.68). A similar observation was made for the African males (n=86) and females (n=84), where no significant difference in 8–OHdG levels was detected (p = 0.053). Thus, from the results obtained in this study, it seems that urinary 8–OHdG levels are not influenced by gender. However, 8–OHdG levels were dramatically influenced by ethnicity. Caucasian males (n=87) excreted 70% higher amounts of 8–OHdG compared to African males (n=86) (p < 0.001). Caucasian females (n=96) also excreted larger urinary 8–OHdG amounts (42%) compared to African females (n=84) (p < 0.001). Therefore, it seems that urinary 8–OHdG levels are dramatically influenced by ethnicity. Finally, urinary 8–OHdG levels were compared to serum ROS levels, but no significant correlation between the measured metabolites was observed (r = –0.045). Hence, urinary 8–OHdG and serum ROS levels are not related in these subjects. Even though the initial aim of this study was to standardise an analytical method to quantify both urinary 8–OHdG and DHN–MA, this could not be achieved due to time constraints. vi The human body has evolved certain defence mechanisms to cope with the high occurrence of free radicals. These radicals are obtained endogenously from the mitochondria, peroxisomes, the cytochrome P450 (CYP 450) system and neutrophils, or exogenously from the environment. Lack of antioxidants and/or increased production of free radicals will result in oxidative stress, which has been implicated in certain human diseases such as hypertension, inflammation, ageing, autoimmunity, atherosclerosis, Parkinson?s disease, cancer and diabetes. Although the initial aim was to standardise a single assay to quantify both 8–OHdG and DHN–MA, this could not be achieved in this study due to the vast difference in the chemical properties of these two metabolites. Following the decision to use two separate assays for the quantification of the mentioned biomarkers, the 8–OHdG assay was standardised and validated. The intrabatch variation of the assay was 4.18% and the interbatch variation was 17.37%. Unfortunately, the DHN–MA assay could not be standardised within the time frame of this study due to experimental difficulties. Therefore, only urinary 8–OHdG and serum ROS levels were quantified. Urinary 8–OHdG levels were measured in 409 participants (209 Caucasians, 101 males and 108 females and 200 Africans, 100 males and 100 females) from the SABPA study. After removal of outliers from the data matrix, the effect of gender and ethnicity was investigated on the measured urinary 8–OHdG levels. No significant difference in the urinary 8–OHdG levels between Caucasian males (n=87) and females (n=96) were observed (p = 0.68). A similar observation was made for the African males (n=86) and females (n=84), where no significant difference in 8–OHdG levels was detected (p = 0.053). Thus, from the results obtained in this study, it seems that urinary 8–OHdG levels are not influenced by gender. However, 8–OHdG levels were dramatically influenced by ethnicity. Caucasian males (n=87) excreted 70% higher amounts of 8–OHdG compared to African males (n=86) (p < 0.001). Caucasian females (n=96) also excreted larger urinary 8–OHdG amounts (42%) compared to African females (n=84) (p < 0.001). Therefore, it seems that urinary 8–OHdG levels are dramatically influenced by ethnicity. Finally, urinary 8–OHdG levels were compared to serum ROS levels, but no significant correlation between the measured metabolites was observed (r = –0.045). Hence, urinary 8–OHdG and serum ROS levels are not related in these subjects. Even though the initial aim of this study was to standardise an analytical method to quantify both urinary 8–OHdG and DHN–MA, this could not be achieved due to time constraints. However, an LC–MS/MS analytical assay was standardised and validated for the quantification of urinary 8–OHdG. The method proved reliable for the quantification of 8–OHdG from urine samples and can thus be used for further studies on oxidative DNA damage. / Thesis (M.Sc. (Biochemistry))--North-West University, Potchefstroom Campus, 2011.
8

Opvoedersekuriteit en sportafrigting by skole : onderwysregtelike perspektief / Doubell T.B.

Doubell, Thomas Burton January 2012 (has links)
Sport by skole is n verlengstuk tot die opvoeding van die kind, en in die meeste goed funksionerende openbare skole vind sportafrigting wel plaas. Sekere kommerwekkende gebeure rakende die onderwysers se regsaanspreeklikheid tydens die afrigting van sport het hierdie studie genoodsaak. Die klem van hierdie studie fokus op die sekuriteit en veiligheid van nopvoeder, veral tydens die afrigting van sport. In die studie is daar na opvoeders verwys in hulle rolle as sportafrigters, wedstrydbeamptes en administrateurs by skole. Hierdie navorsing val binne die vakgebied Onderwysreg en die opvoeders se sekuriteit en veiligheid word onder andere vanuit n gemeenregtelike perspektief bespreek. Om die studie geldig te maak, is al die rolspelers wat by sportafrigting by die skole betrokke is, by die studie ingesluit. Die Grondwet, onderwyswetgewing, beroepsveiligheid en –gesondheidswetgewing, tersaaklike regspraak en die gemene reg is as regsdeterminante ontleed. Daar is veral in die bespreking van die gemene reg gefokus op deliktuele aanspreeklikheid as regsdeterminant. In die studie is n kwalitatiewe ondersoek na opvoeders se persepsies gedoen. Daar is gefokus op deelnemers in die onderwys in n spesifieke geografiese area is, en die hele spektrum van rolspelers is betrek. Een prominente bevinding van die studie is dat opvoeders gretig is om meer inligting oor die regsaspekte rakende sportafrigting te bekom. Dit is vir die meeste deelnemers n onbekende veld en hulle is van mening dat indien hulle meer ingelig is, dit n groot bydrae sal lewer tot hulle eie veiligheid en sekuriteit, sowel as dié van leerders. Die sentrale tema van die studie is die sekuriteit en veiligheid van die opvoeders. Die deelnemers is daarvan oortuig dat daar in die opleiding van afrigters groter klem geplaas moet word op die uitbou van regskennis. Opvoeders het n passie vir die afrigting van sport en die klem is op die ontwikkeling van die leerder. / Thesis (M.Ed.)--North-West University, Potchefstroom Campus, 2012.
9

Urinary 1,4–dihydroxynonene mercapturic acid (DHN–MA) and 8–hydroxy–2'–deoxyguanosine (8–OHdG) as markers of oxidative damage : the SABPA study / by Leandrie Steenkamp

Steenkamp, Leandrie January 2010 (has links)
The human body has evolved certain defence mechanisms to cope with the high occurrence of free radicals. These radicals are obtained endogenously from the mitochondria, peroxisomes, the cytochrome P450 (CYP 450) system and neutrophils, or exogenously from the environment. Lack of antioxidants and/or increased production of free radicals will result in oxidative stress, which has been implicated in certain human diseases such as hypertension, inflammation, ageing, autoimmunity, atherosclerosis, Parkinson?s disease, cancer and diabetes. Although the initial aim was to standardise a single assay to quantify both 8–OHdG and DHN–MA, this could not be achieved in this study due to the vast difference in the chemical properties of these two metabolites. Following the decision to use two separate assays for the quantification of the mentioned biomarkers, the 8–OHdG assay was standardised and validated. The intrabatch variation of the assay was 4.18% and the interbatch variation was 17.37%. Unfortunately, the DHN–MA assay could not be standardised within the time frame of this study due to experimental difficulties. Therefore, only urinary 8–OHdG and serum ROS levels were quantified. Urinary 8–OHdG levels were measured in 409 participants (209 Caucasians, 101 males and 108 females and 200 Africans, 100 males and 100 females) from the SABPA study. After removal of outliers from the data matrix, the effect of gender and ethnicity was investigated on the measured urinary 8–OHdG levels. No significant difference in the urinary 8–OHdG levels between Caucasian males (n=87) and females (n=96) were observed (p = 0.68). A similar observation was made for the African males (n=86) and females (n=84), where no significant difference in 8–OHdG levels was detected (p = 0.053). Thus, from the results obtained in this study, it seems that urinary 8–OHdG levels are not influenced by gender. However, 8–OHdG levels were dramatically influenced by ethnicity. Caucasian males (n=87) excreted 70% higher amounts of 8–OHdG compared to African males (n=86) (p < 0.001). Caucasian females (n=96) also excreted larger urinary 8–OHdG amounts (42%) compared to African females (n=84) (p < 0.001). Therefore, it seems that urinary 8–OHdG levels are dramatically influenced by ethnicity. Finally, urinary 8–OHdG levels were compared to serum ROS levels, but no significant correlation between the measured metabolites was observed (r = –0.045). Hence, urinary 8–OHdG and serum ROS levels are not related in these subjects. Even though the initial aim of this study was to standardise an analytical method to quantify both urinary 8–OHdG and DHN–MA, this could not be achieved due to time constraints. vi The human body has evolved certain defence mechanisms to cope with the high occurrence of free radicals. These radicals are obtained endogenously from the mitochondria, peroxisomes, the cytochrome P450 (CYP 450) system and neutrophils, or exogenously from the environment. Lack of antioxidants and/or increased production of free radicals will result in oxidative stress, which has been implicated in certain human diseases such as hypertension, inflammation, ageing, autoimmunity, atherosclerosis, Parkinson?s disease, cancer and diabetes. Although the initial aim was to standardise a single assay to quantify both 8–OHdG and DHN–MA, this could not be achieved in this study due to the vast difference in the chemical properties of these two metabolites. Following the decision to use two separate assays for the quantification of the mentioned biomarkers, the 8–OHdG assay was standardised and validated. The intrabatch variation of the assay was 4.18% and the interbatch variation was 17.37%. Unfortunately, the DHN–MA assay could not be standardised within the time frame of this study due to experimental difficulties. Therefore, only urinary 8–OHdG and serum ROS levels were quantified. Urinary 8–OHdG levels were measured in 409 participants (209 Caucasians, 101 males and 108 females and 200 Africans, 100 males and 100 females) from the SABPA study. After removal of outliers from the data matrix, the effect of gender and ethnicity was investigated on the measured urinary 8–OHdG levels. No significant difference in the urinary 8–OHdG levels between Caucasian males (n=87) and females (n=96) were observed (p = 0.68). A similar observation was made for the African males (n=86) and females (n=84), where no significant difference in 8–OHdG levels was detected (p = 0.053). Thus, from the results obtained in this study, it seems that urinary 8–OHdG levels are not influenced by gender. However, 8–OHdG levels were dramatically influenced by ethnicity. Caucasian males (n=87) excreted 70% higher amounts of 8–OHdG compared to African males (n=86) (p < 0.001). Caucasian females (n=96) also excreted larger urinary 8–OHdG amounts (42%) compared to African females (n=84) (p < 0.001). Therefore, it seems that urinary 8–OHdG levels are dramatically influenced by ethnicity. Finally, urinary 8–OHdG levels were compared to serum ROS levels, but no significant correlation between the measured metabolites was observed (r = –0.045). Hence, urinary 8–OHdG and serum ROS levels are not related in these subjects. Even though the initial aim of this study was to standardise an analytical method to quantify both urinary 8–OHdG and DHN–MA, this could not be achieved due to time constraints. However, an LC–MS/MS analytical assay was standardised and validated for the quantification of urinary 8–OHdG. The method proved reliable for the quantification of 8–OHdG from urine samples and can thus be used for further studies on oxidative DNA damage. / Thesis (M.Sc. (Biochemistry))--North-West University, Potchefstroom Campus, 2011.
10

Opvoedersekuriteit en sportafrigting by skole : onderwysregtelike perspektief / Doubell T.B.

Doubell, Thomas Burton January 2012 (has links)
Sport by skole is n verlengstuk tot die opvoeding van die kind, en in die meeste goed funksionerende openbare skole vind sportafrigting wel plaas. Sekere kommerwekkende gebeure rakende die onderwysers se regsaanspreeklikheid tydens die afrigting van sport het hierdie studie genoodsaak. Die klem van hierdie studie fokus op die sekuriteit en veiligheid van nopvoeder, veral tydens die afrigting van sport. In die studie is daar na opvoeders verwys in hulle rolle as sportafrigters, wedstrydbeamptes en administrateurs by skole. Hierdie navorsing val binne die vakgebied Onderwysreg en die opvoeders se sekuriteit en veiligheid word onder andere vanuit n gemeenregtelike perspektief bespreek. Om die studie geldig te maak, is al die rolspelers wat by sportafrigting by die skole betrokke is, by die studie ingesluit. Die Grondwet, onderwyswetgewing, beroepsveiligheid en –gesondheidswetgewing, tersaaklike regspraak en die gemene reg is as regsdeterminante ontleed. Daar is veral in die bespreking van die gemene reg gefokus op deliktuele aanspreeklikheid as regsdeterminant. In die studie is n kwalitatiewe ondersoek na opvoeders se persepsies gedoen. Daar is gefokus op deelnemers in die onderwys in n spesifieke geografiese area is, en die hele spektrum van rolspelers is betrek. Een prominente bevinding van die studie is dat opvoeders gretig is om meer inligting oor die regsaspekte rakende sportafrigting te bekom. Dit is vir die meeste deelnemers n onbekende veld en hulle is van mening dat indien hulle meer ingelig is, dit n groot bydrae sal lewer tot hulle eie veiligheid en sekuriteit, sowel as dié van leerders. Die sentrale tema van die studie is die sekuriteit en veiligheid van die opvoeders. Die deelnemers is daarvan oortuig dat daar in die opleiding van afrigters groter klem geplaas moet word op die uitbou van regskennis. Opvoeders het n passie vir die afrigting van sport en die klem is op die ontwikkeling van die leerder. / Thesis (M.Ed.)--North-West University, Potchefstroom Campus, 2012.

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